Due to the fact that diallylamine hydrochloride polymers are nowadays easily producible by polymerization of diallylamine hydrochloride monomers in an aqueous solution in the presence of a radical polymerization catalyst and that they are water-soluble cationic polymers, diallylamine hydrochloride polymers have been industrially manufactured and their use has been proposed in diverse fields such as in metal protection agents, inkjet recording applications and electronic materials.
However, since diallylamine hydrochloride polymers contain a halogen, they could be difficult to use in some applications such as ceramic binders and any applications that involve contact with a metal where the halogen may cause corrosion. Therefore, as use of diallylamine hydrochloride polymers or the likes is increasingly contemplated in the field of fine chemicals, non-halogen polymers are beginning to be sought after.
Known methods for producing such a polymer include a method in which an alkali metal acetate is added to a diallylamine hydrochloride polymer and the resulting mixture is subjected to ion-exchange membrane electrodialysis to remove chloride ions, which are halogen, and to obtain a non-halogen diallylamine acetate polymer (Patent Document 1). Also known is a method in which a diallylamine hydrochloride polymer is desalted by neutralizing it with sodium hydroxide to remove chloride ions and to obtain a free diallylamine polymer (Patent Document 2). However, these methods are time-consuming and expensive, and moreover, they may not be able to produce a completely halogen-free polymer.